KR20110139719A - Fluctuating gear ratio limited slip differential - Google Patents

Abstract

A variable gear ratio differential limiter assembly 12 is provided that includes a differential case 14 and a pair of side gears 20 installed within the differential case. Each of the side gears has a tooth having a first toothed surface. The differential window further comprises a pinion shaft installed in the differential case and a plurality of pinions 18 supported by the pinion shaft 16. The pinions are configured to engage with the pair of side gears and each of the pinions has teeth with a second sprinkled surface. The first and second sprinkling surfaces are configured to move in an controlled manner the operating surface defining all the contact points between the first sprinkling surface of the side gears and the second sprinkling surface of the pinion.

Description

Variable gear ratio differential limiter {FLUCTUATING GEAR RATIO LIMITED SLIP DIFFERENTIAL}

This application claims priority to US patent application Ser. No. 12 / 403,141, filed Mar. 12, 2009, which is hereby incorporated by reference in its entirety.

The present invention relates to a gear set, wherein each gear of the gear set defines an contact point between the tooth flank of the first gear of the gear set and the tooth flank of the second gear of the gear set. It has a root surface configured to move a plane of action in a predefined and / or controlled manner.

As described in U.S. Patent No. 3,631,736, the tooth profile of gears operating in parallel axes (e.g., cylindrical gears) is that the common normal at all points of contact is on the centerline. It is a kinematic requirement if one tooth drives another tooth at a constant angular velocity ratio, as the gear rotates, a pair of teeth contact each other at different positions. The location of all possible contact points for the pairs is called the path of contact, which is a straight or curved line segment and terminates at the end of the gear teeth. The three curves involved in the gear design are the teeth of the first gear, the teeth of the second gear and the contact path. When the air, one of the curved lines may determine the other two. In particular, when the contact path shown by the given curve and can be determined uniquely are teeth of the two gears.

In the cylindrical gear device, the gear set includes a first tooth, a first center point, a first gear having a first outer radius (from the first center point to the circumference of the first gear), the second tooth shape, and the first gear. A first gear having a center point and a second outer radius (from the second center point to the circumference of the second gear). Pitch radii is the spacing between the pitch point and each gear center (ie, the first center point and the second center point). In other words, the pitch radii specify the spacing between the pitch point and each gear axis. As the first and second gears rotate, the profile curves of the first and second gears come into contact with each other at different locations and also the locations of all successive contact points are in contact path (i.e. line of action). of action).

When each contact point is located at a predetermined distance from the pitch point and a pressure angle from the horizontal line normal to the line connecting the first and second center points, each contact point is in polar coordinates. I can display it. The first and second tooth shapes for the gears may have a first and second radius of curvature having a first and a second length, respectively.

The first and second gears (e.g., with the pinion gear in the differential) move the operating surface defining the contact points between the toothed surface of the first gear and the toothed surface of the second gear in a predefined and / or controlled manner. It may be desirable to use a toothed geometry of the side gear).

It is an object of the present invention to provide a variable gear ratio differential limiter using sprinkled geometry of first and second gears (e.g., pinion gears and side gears in differentials).

A gear set may be provided that may include a first gear having a first sprinkled surface and a second gear having a second sprinkled surface. The first sprinkled surface and the second sprinkled surface may be configured to move the operating surface defining contact points between the first sprinkled surface and the second sprinkled surface in a predefined and / or controlled manner.

A variable gear ratio differential limiter assembly is provided that can include a differential case and a pair of side gears installed within the differential case. Each of the side gears may have teeth with a first toothed surface. The differential assembly may further comprise a pinion shaft installed in the differential case and a plurality of pinions supported by the pinion shaft. The pinions may be configured to engage with the pair of side gears and each of the pinions may have teeth with a second root surface. The first and second sprinkling surfaces are configured to move the operating surface defining the contact points between the first sprinkling surface of the side gears and the second sprinkling surface of the pinion in a predefined and / or controlled manner.

Determining a desired torque bias and the portion of the desired torque to be transmitted to the first gear, and defining the operating surface to be the portion of the desired torque and the desired torque to be transmitted to the first gear There is provided a method for designing a gearset, comprising determining a predetermined movement. The method includes determining contact points between a first gear and a second gear defined by the actuating surface, and forming sprinkled surfaces of the first and second side gears corresponding to the contact points determined by the actuating surface. Determining further.

According to the present invention, there is provided a variable gear ratio differential limiting device using the sprinkled geometry of the first and second gears.

1 is a schematic cross-sectional view of a differential device according to an embodiment of the present invention.
2 is a schematic view of an operating surface between a first gear and a second gear in accordance with an embodiment of the present invention.
3 is a perspective view of a prior art bevel gear having a gear tooth surface;
4 is a schematic illustration of a gear base cone of the bevel gear of FIG. 3.
5 is a perspective view of a pinion having a modified gear sprinkled surface according to one embodiment of the present invention.
6 is a perspective view of a side gear having a modified gear sprinkled surface according to one embodiment of the invention.
FIG. 7 illustrates an example of computer modeling with a modified gear tooth surface in accordance with one embodiment of the present invention. FIG.

Embodiments of the present invention will be described by way of example with reference to the accompanying drawings.

Embodiments of the present invention will be described in detail with reference to the examples described herein and described in the accompanying drawings. While the invention has been described in connection with embodiments, it will be understood that they are not intended to limit the invention to these embodiments. On the contrary, the invention covers alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as embodied by the appended claims.

1 is a schematic cross-sectional view of a gear set 10 according to an embodiment of the present invention. As shown in FIG. 1, gear set 10 may be used for differential device 12. For example, differential device 12 may include a differential limiting device. The gearset 10 of the present invention can be used to provide an uneven distribution of torque to two side gears of the differential limiter 12 for a wheel drive vehicle. The differential limiter 12 may comprise a variable gear ratio differential limiter in some embodiments.

In particular, the function of the variable gear ratio differential limiter is such that a periodic gear ratio change (e.g., fluctuation) between the pinions and the side gears during engagement between the pinions and the side gears connected with the pinions with an odd gear ratio shift period in one revolution. When the gear ratio between the pinions and one side gear reaches a maximum, the gear ratio between the pinion and the other side gear reaches a minimum, so that an uneven distribution of torque may occur on the two side gears.

With continued reference to FIG. 1, the differential device 12 may include a differential case 14 and a pinion shaft 16. The differential case 14 may be driven by an input shaft (not shown). The pinion shaft 16 may comprise a cross shaft or a straight shaft and may also be fixed inside the differential case 14. The differential device 12 may further include a pinion gear 18 and a side gear 20. Pinion gear 18 may be supported by pinion shaft 16 and configured to engage side gear 20. The pinion gear 18 and the side gear 20 may each include a plurality of gears (pairs). A spherical thrust washer 22 may be disposed between the rear side of the pinion gear 18 and the differential case 14. A flat thrust washer 24 may be disposed between the rear side of the side gear 20 and the differential case 14. The differential device 12 is suitable for allowing different rotational speeds to be achieved between the side gears 20 arranged in the differential case 14.

The gear set 100 of the present invention may include first and second gears. According to an embodiment of the present invention, the first gear may include a pinion gear 18, and the second gear may include a side gear ( 20. Although the gear set 10 is described as having first and second gears including the pinion gear 18 and the side gear 20, the first part of the gear set 10 is described. The first and second gears may include any number of different gears, which are also included within the spirit and scope of the present invention: The first gear may comprise teeth having a first root surface, and the second gear may comprise a second gear. It may include teeth with tooth roots.

The geometry of the sprinkling surfaces of the first and second gears (for example, the pinion gear 18 and the side gear 20) of the present invention may be configured to move the working surface in a predefined manner. In other words, the movement of the working surface can be controlled and / or optimized movement. The working surface may also be called the working surface. The working surface defines the contact points between the first sprinkling surface of the first gear of the gearset and the second sprinkling surface of the second gear of the gearset. The tooth surface of the first gear is represented by successive portions of the working surface that move relative to the coordinate system associated with the first gear. The tooth surface of the second gear is represented by successive parts of the working surface that move relative to the coordinate system associated with the second gear.

Referring to FIG. 2, a schematic diagram of the line of action 26 ₁ , 26 ₂ , or 26 ₃ between a first gear (eg pinion gear 18) and a second gear (eg side gear 20) is shown on the operating surface. Described as background for understanding. The gears 18 and 20 may be in contact along the line of action 26 ₁ , 26 ₂ , or 26 ₃ . As described in the figure, the line of action 26 ₁ , 26 ₂ , or 26 ₃ does not stop, but moves in a predefined and / or controlled and / or optimized manner. For example, according to a predefined and / or controlled and / or optimized manner of movement of the line of action, a second position (eg, 26 at the first position of the line of action (eg, the position of line of action 26 ₁ , 26 ₂ )). ₂ , or 26 ₃ ). The direction of the line of action at the first position may be substantially parallel to the direction of the line of action at the second position. Movement of the line of action causes the gearset to transmit more torque to one of the pair of tires (eg, controlled by the side gear 20). The amount of torque to be transmitted to a pair of tires (e.g., right and left tires) depends on the surfaces on which the tires act and / or the amount of static traction between the tires and the surfaces. The pinion 18 may have a center point O _p and the side gear 20 may also have a center point O _g . Centerline 28 intersects between center points O _p and O _g . The pitch point P ₁ , P ₂ or P ₃ is the intersection of the center line 28 and the working line 26. The radius of the base cylinder of the pinion 18 and the side gear 28 (r _{b .p} , r _{b .g} , respectively) is the line of action 26 ₁ , 26 ₂ at the center points O _p and O _g, respectively. , Or 26 ₃ ). Line 30 extends perpendicular to centerline 28 via pitch point P ₁ , P ₂ or P ₃ . The profile angle φ _n is the angle between the line 30 and the line of action 26 ₁ , 26 ₂ , or 26 ₃ . Since the line of action 26 ₁ , 26 ₂ , or 26 ₃ is used for the two-dimensional geometry and the working surface is used for the three-dimensional geometry, FIG. 2 is controlled for the pinion 18 and the side gear 20 and It may be useful to simulate working surfaces that move in an optimized manner.

The torque ratio between the left and right tires may be based on the surfaces on which the tires act and / or the amount of static friction between the tires and the surfaces. For the trajectories of known contact points, the geometry of the root surface can be determined. According to one embodiment of the invention, the actuating surface moving in a controlled and / or optimized manner may be based on and / or correspond to the rotation of the pinion gear 18. For example, in one embodiment the actuating surface may move at a constant speed in accordance with a constant rotation of the pinion gear 18. In another example, in accordance with a predefined and / or controlled manner of movement of the operating surface, the operating surface may be configured to move from the first position to the second position. The direction of the working surface in the first position may be substantially parallel to the direction of the working surface in the second position. The movement of the working surface may be configured to transmit a progressively increasing torque to the side gear 20 (eg, the second gear of the gearset 10). In other cases, the movement of the operating surface may also be configured to transmit progressively decreasing torque to the side gear 20 (ie, the second gear of the gearset 10). In this manner, the movement at which the operating surface is predefined and / or controlled transmits a first amount of torque to the first side gear 20 (eg on the right side of the vehicle) and also (eg on the left side of the vehicle). ) May be configured to transmit a second amount of torque to the second side gear 20, wherein the first and second amounts of torque are different. Thus, each of the pair of side gears 20 can be configured to rotate at different rotational speeds.

In other embodiments, the working surface may be moved in other ways, predefined and / or controlled. For example, the working surface may be accelerated or decelerated in accordance with the engagement of the toothed surface of the first gear (eg pinion gear 18) with the toothed surface of the second gear (eg side gear 20). The working surface can be accelerated or decelerated from the pitch point toward the axis of the gear (pinion gear 18 or side gear 20), rather than moving at a constant speed. In this way, the working surface is based on the engagement of short teeth (eg working teeth) on the first and second gears (eg pinion gear 18 and side gear). can do.

Teeth on the gears (eg, pinion gear 18 and side gear 20) can be used for different purposes. For example, tall teeth on pinion gear 18 and / or side gear 20 may assist in reengagement of low teeth on gears 18 and 20. . The reservoirs are working and / or working teeth (ie teeth transmitting torque). The reservoirs are configured to transfer torque from the first gear (eg pinion gear 18) to the second gear (eg side gear 20) when the gears are engaged. On the other hand, the cocoons may not transmit torque. The cocoons may be configured to be higher than the bottom and may also have a smaller angle relative to their tooth surface to provide recombination of the working teeth on the first and second gears. Because of the cocoons and reservoirs on the gears of the gearset 10 (e.g., pinion gear 18 and side gear 20), there may be no transmission of smooth torque, resulting in noise and shocks that need to be absorbed. . Noise reduction may be the biggest consideration in vehicle design. The modified toothed geometry of the present invention can be configured to help reduce noise by eliminating the impact that pinion and side gear devices may receive during engagement.

A single group of teeth may include one cocoon (ie, teeth configured to assist in recombination between the gears) and one or more teeth (ie, a torque transmitting task and / or working teeth). Each group of teeth has an odd number of teeth. For example, there may be three teeth in each group. Although three teeth are mentioned in the detailed description, the number of teeth may be larger in other embodiments of the present invention. Although a larger number of teeth can achieve more torque bias, the larger number of teeth requires more space for the gearset 10 and also limits the size of the differential housing (e.g., differential case 14). In this embodiment, three teeth are included in each group. Under the rotation (ωp) of a gear having teeth of the N _gr group (e.g., pinion gear 18), the period of gear ratio variation is ωp / N _gr . The number of teeth in each period corresponds to the number of pitches included in each period. Movement of the working surface is only related to a single group of work and / or working teeth (ie short teeth), not to cocoons.

When the first and second gears (eg, pinion gear 18 and side gear 20) of the gear set 10 rotate, the reservoirs can deviate from contact with each other and the first gear (eg, pinion ( 18) are combined to contact the teeth of the second gear (eg, side gear 20) to help the teeth of the next pair of first and second gears engage, and then the next pair of operations. Teeth can be combined. In the stage where the cocoon of the first gear is in contact with the teeth of the first gear or the cocoon of the second gear is in contact with the teeth of the first gear, the cocoons may be exposed to impact, which may cause the cocoons to fail. In order to eliminate and / or significantly reduce the impact of the cocoon, the following movement of the working surface may be beneficial. First, when the steps are disengaged or just before they are disengaged, the instantaneous working surface may set its speed of movement in the direction of A (FIG. 2) at the very moment corresponding to the start of engagement of the second pair of steps. Start with the value down to zero. Further, the acceleration of the movement of the momentary working surface in the direction of A (Fig. 2) becomes equal to zero at the beginning and the end of the engagement of the cocoon, reaching a predetermined constant value between the predetermined value and zero. One solution to the movement of the working surface is that the instantaneous working surface does not move at the end of the engagement of the pinion gear 18 and the side gear 20 (ie the working teeth).

Due to the corresponding variations in spurs on the first and second gears (e.g. pinion gear 18 and side gear 20), the desired and / or controlled and / or defined instantaneous Movement can be achieved. In accordance with the present invention, toothed surfaces for the first and second gears (eg, pinion gear 18 and side gear 20) can be designed to provide the desired acceleration and / or deceleration of the operating surface. .

As described in the background, the cylindrical gear may use the pitch radii and the length of the radius of the bend to determine the geometry and / or profile of the sprinkling surfaces of the gears that make up the gear set. Conversely, bevel gears may use a pitch cone instead of the length of the radius of the pitch and the radius of the bend to determine the geometry of the root surfaces of the bevel gears that make up the gearset. The geometry of the sprinkling surfaces of the first and second gears (eg, pinion gear 18 and side gear 20) of the present invention may be represented by a spiral cone pitch surface. The portion of the tooth located outside of the helical cone pitch surface is called an addendum. Similarly, the portion of the tooth located between the helical pitch cone surface and the fillet cone surface may be called a dedendum. In order to derive the equation for the modified tooth plane of the gears of the invention, one can use the derivation of the equation for the tooth plane of a conventional (eg prior art) bevel gear.

Referring to FIG. 3, there is shown a perspective view of a prior art bevel gear 32 having a gear tooth surface G. FIG. Generation of the gear tooth surface G of the conventional bevel gear 10 can be interpreted as rolling without sliding of the surface 34 on the gear base cone 36 shown in FIG. Thus, the appearance of the gear sprinkled surface G can be represented by the locations of the straight line E _g in the tangent plane 34 through the vertex 38. If the surface 34 rolls over the gear base cone 36, it is tangent to the gear base cone 36.

The position vector r _g represents X _g , Y _g and Z _g of the points on the root surface. The position vector r _g of the point M of the root surface G may represent a sum of three vectors. In particular, the equation for the position vector r _g is:

r _g = A + B + C , where the vectors A , B and C are equivalent to

(식1)

(Eq. 1)

(식2)

(Eq. 2)

(식3),

(Eq. 3),

는 이뿌리면(G)의 변수들이다.Where i , j and k represent unit vectors along the axes X _g , Y _g , Z _g (ie component "i" is a vector of length l specified along axis "X _g "; component " j "is a vector of length l specified along axis" Y _g "; and component" k "is a vector of length l specified along axis" Z _g ") and U _g is a vertex (38). ) Is the distance measured to the projection of M on the Z _g axis. U _g with

Are variables of the root surface (G).

Substituting vectors A , B and C into the equation r _g = A + B + C , we can derive the equation (4) for the root surface (G) for the pinion gear (18):

(식4)

(Eq. 4)

" 및 사이드 기어에 대해서는 "

"). 사이드 기어(20)에 대한 이뿌리면(G)에 대한 식(식 4.1)은 행렬로 유도할 수 있다:The same formula can be used for bevel gears and pinions and side gears. However, the equations are not the same. For example, equations may have other coefficients (eg, for pinions, "

"And about the side gear"

The equation for root surface G for side gear 20 (Equation 4.1) can be derived from the matrix:

(식4.1)

(Equation 4.1)

+

=90°보통 관측된다. 따라서, 피치각

는 피니언의 피치각

의 항으로서

=90°-

로 나타낼 수 있다. 이 방식에서, 미지항(unknowns)의 숫자가 하나의 미지항으로 줄어든다(즉, 두 개의 변수

+

가 아니라, 단지 변수

만이 미지항으로 남는다). 식 4.1에 대입한 후, 사이드 기어의 이뿌리면에 대한 수식에 대해 이 식(식4.2)은 행렬 형태로 표현할 수 있다.Uniformity in Differential Applications

+

= 90 ° Usually observed. Thus, pitch angle

Is the pitch angle of the pinion

As a term

= 90 °-

It can be represented as. In this way, the number of unknowns is reduced to one unknown (ie two variables).

+

Not just variables

Only remains unknown). After substituting Eq. 4.1, this equation (Equation 4.2) can be expressed in the form of a matrix for the equation for the root surface of the side gear.

(식 4.2)

(Equation 4.2)

을 기반으로 할 수 있는데, u 는 피니언 대 사이드 기어 결합의 이빨 비를 나타낸다.The further reduction of the total number of unknown ports is equivalent to

U is the tooth ratio of the pinion to side gear coupling.

(식 4.3)

(Equation 4.3)

에 대한 식은 통상(예컨대, 선행기술) 베벨 기어에 대한 위치벡터 r _g 에 대한 식으로부터 유도할 수 있다. 수정된 위치벡터

에 대한 식은, 수정된 위치벡트

에 다음 식에서 주어져 있듯이, 기어의 회전각도

의 함수로서 콘(cone) 각도

를 고려할 수 있다:Referring to FIG. 5, the modified gear tooth surface G _mod for the pinion gear 18 is shown. Referring to FIG. 6, the modified gear tooth plane G _mod geometry for the side gear 20 is shown. The position vector r _g representing the modified gear tooth plane G _mod is represented by another determinant. The difference in the determinant for the modified gear tooth plane (G _mod ) is the movement of the operating surface (ie the operating surface defining all the contact points between the first and second tooth planes of the gears constituting the gearset). It is due to. Movement of the working surface enables torque biasing. The operating surface may move in a predefined and / or controlled manner as described herein. Position vector for bevel gear of the present invention

The equation for can usually be derived from the equation for the position vector r _g for the bevel gear (eg prior art). Modified position vector

The expression for is the modified position vector

As given in the following equation, the angle of rotation of the gear

Cone angle as a function of

You can consider:

(식5)

(Eq. 5)

Similar to being able to derive Equation 4.2 from Equation 4, Equation 4 for the pinion sprinkled surface allows the equation for the side gear sprinkled surface (Equation 5.1) to be matrixed:

(식5.1)

(Equation 5.1)

을 기반으로 할 수 있는데, u 는 피니언 대 사이드 기어 결합의 이빨 비를 나타낸다.The further reduction of the total number of unknown ports is equivalent to

U is the tooth ratio of the pinion to side gear coupling.

(Equation 5.2)

에 대한 식의 유도에 사용할 수 있다. 함수

대

는 선형함수일 수 있고, 또한

의 형태로 나타낼 수 있는데, 소정의 상수는 "a"로 나타낸다. 이 상수 a는 원하는 토크 바이어스의 항으로 결정하여 나타낼 수 있다.Another solution is a modified position vector representing the geometry of the modified gear sprinkled surface G _mod as is well known to those skilled in the art.

Can be used to derive the equation for. function

versus

Can be a linear function,

It can be expressed in the form of, a predetermined constant is represented by "a". This constant a can be determined and expressed in terms of the desired torque bias.

(식 4.1 참조)는 μ=0 일 때의 값

에서 이빨들이 정합에서 분리될 때의 값

으로 변할 수 있다. 비율

/

는 T _bias 와 동일하다(즉, 균등식

/

=T _bias 는 유효하다). 궁극적으로, 변수"a"의 원하는 rkqqtdms 다음의 식으로부터 계산할 수 있다:The variable "a" affects the actual shape of the toothed surface of the pinion 18 and the side gear 20. The restriction on the variable "a" is double. First, none of the sprinkles of the pinion 18 or the side gear 20 are present under the corresponding base cone. Second, no tooth points are allowed in the outer cone. The range for the value of the variable "a" can be calculated based on these limits. When the side gear rotates, the toothed surface of the side gear (for example, side gear 20) is engaged with the gear (for example, pinion 18) that matches. The pinion that matches while the side gear 20 rotates at a predetermined angle (μ, μ is the rotation angle of the side gear 20 where the toothed surface of the side gear 20 is matched with the toothed surface of the pinion 18). The contact of the tooth root surface of 18 with the tooth root surface of the side gear 20 is maintained. The desired torque bias through the differential (differential device 12) can be denoted by T _bias . The desired torque bias is angled to achieve a T _bias .

(See Equation 4.1) is the value when μ = 0.

When teeth are separated from registration in

Can be changed to ratio

Of

Is equal to the T _bias (i.e. equality

Of

= T _bias Is valid). Ultimately, the desired rkqqtdms of variable "a" can be calculated from the following equation:

(식 5.3)

(Equation 5.3)

는 기어의 회전각도

의 선형함수이면(즉,

=

), 수정된 위치벡터

에 대한 식은 다음 식으로 줄어들 수 있다:Cone angle

Rotation angle of gear

Is a linear function of (i.e.

=

), Modified position vector

The expression for can be reduced to

(식 6)

(Equation 6)

가 기어의 회전각도

의 선형함수가 되도록 함으로써, 함수

는 가장 단순한 함수가 될 수 있다. 일반적으로, 다른 실시예들에서는 기어의 회전각도

의 함수로서 콘 각도

는 보다 복잡할 수 있다. 회전각도

의 함수로서 콘 각도

의 함수는 소정의 차동장치 응용에 대해 필요한 및/또는 바람직한 차동장치에 의한 토크 바이어싱에 따르게 된다. 선형함수

는 현실적인 함수이다. 수정된 이뿌리면(G_mod)의 컴퓨터 모델링의 예를 도 7에 도시하였다. 제1 및 제2기어(예컨대, 피니언 기어(18)와 사이드 기어(20))들의 이뿌리면의 기하학적 구조는 제1 및 제2기어들에 대한 설계 변수들의 항으로 나타낼 수 있다. 본 기술분야의 당업자에게 잘 알려졌듯이 통상적인 공학적 방정식을 사용할 수 있다.Cone angle

Rotation angle of gear

Function so that the linear function of

Can be the simplest function. In general, in other embodiments the angle of rotation of the gear

Cone angle as a function of

May be more complex. Rotation angle

Cone angle as a function of

The function of depends on the torque biasing by the required and / or desired differential for a given differential application. Linear function

Is a realistic function. An example of computer modeling of the modified root surface (G _mod ) is shown in FIG. 7. The geometry of the sprinkling surfaces of the first and second gears (eg, pinion gear 18 and side gear 20) can be represented in terms of design variables for the first and second gears. As is well known to those skilled in the art, conventional engineering equations can be used.

Also provided is a method for designing a gearset 10 according to the invention. The method includes determining a desired torque bias and a desired portion of torque to transmit to the first gear; Determining a defined movement of the operating surface to produce the desired torque bias and a desired portion of torque to be transmitted to the first gear; Determining contact points between the first gear and the second gear defined by the operating surface; And determining the sprinkling surfaces of the first and second gears corresponding to the contact points defined by the operating surface.

The foregoing description of specific embodiments of the present invention has been presented for purposes of explanation. The description is not intended to limit the invention to the above form, and various modifications and variations are possible in view of the above descriptions. Embodiments have been selected to illustrate the principles of the invention and its practical application, and to enable any person skilled in the art to utilize the various embodiments having the various modifications suitable for the invention and also for practical use. The present invention has been described in considerable detail in the above description, and also by reading and understanding the above description, those skilled in the art will recognize various changes and modifications of the invention. As long as such various changes and modifications fall within the scope of the appended claims, these changes and modifications are included in the present invention. It is intended that the scope of the invention be defined by the claims appended hereto and their equivalents.

Claims (25)

A first gear having a first root surface;
Including a second gear having a second root surface,
And the first sprinkling surface and the second sprinkling surface are configured to move the operating surface defining a contact point between the first sprinkling surface and the second sprinkling surface in a controlled manner. The gear set of claim 1, wherein the movement of the operating surface is configured to transmit progressively increasing torque to the second gear. The gear set of claim 1, wherein the movement of the operating surface is configured to transmit a progressively decreasing torque to the second gear. The gear set of claim 1, wherein the first gear comprises a pinion. The gear set of claim 4, wherein the second gear comprises a first side gear. 6. The gear set of claim 5, further comprising a third gear, wherein the third gear comprises a second side gear. 7. The method of claim 6, wherein the movement of the operating surface is configured to transmit a first amount of torque to the first side gear and to transfer a second amount of torque to the second side gear. Torques are different from each other. The gear set according to claim 1, wherein the movement of the operating surface corresponds to the rotation of the first gear. 9. The gear set according to claim 8, wherein the movement of the working surface is at a constant speed. 9. The gear set of claim 8, wherein the movement of the operating surface comprises acceleration and deceleration in accordance with the engagement of the first and second toothed surfaces. The gear set of claim 1, wherein each of the first and second gears has at least one working tooth configured to transfer torque from the first gear to the second gear when engaged. 12. The gear set of claim 11, wherein each of the first and second gears has at least one cocoon higher than the working tooth. 13. The gear set of claim 12, wherein the movement of the working surface is based on a combination of working teeth on the first gear and working teeth on the second gear. The gearset of claim 1, wherein the first and second sprinkling surfaces are derived from a pitch cone. The method of claim 1, wherein the first gear has a first coordinate system, the second gear has a second coordinate system, the operating surface is configured to move relative to the first coordinate system and the second coordinate system. Gear set. The method of claim 1, wherein the operating surface is configured to move from the first position to the second position, and wherein the direction of the operating surface in the first position is substantially parallel to the direction of the operating surface in the second position. Gear set. A differential case;
A pair of side gears each having teeth having a first sprinkled surface and installed inside the differential case;
A pinion shaft installed inside the differential case;
A plurality of pinions each having teeth having a second sprinkled surface and supported by the pinion shaft and configured to engage with the pair of side gears;
And the first and second sprinkling surfaces are configured to move the operating surface defining a contact point between the first sprinkling surface and the second sprinkling surface in a controlled manner. 18. The method of claim 17, wherein the movement of the operating surface is configured to transmit a first amount of torque to one of the pair of side gears and to transfer a second amount of torque to another side gear. And the second amount of torques are different from each other. 18. The variable gear ratio differential limiting device according to claim 17, wherein the movement of the operating surface corresponds to rotation of the plurality of pinions. 18. The variable gear ratio differential limiting device according to claim 17, wherein the movement of the operating surface is at a constant speed. 18. The variable gear ratio differential limiting device according to claim 17, wherein the movement of the operating surface includes acceleration or deceleration according to the combination of the pair of side gears and the plurality of pinions. 18. The variable gear ratio differential limiting device according to claim 17, further comprising an input shaft configured to drive the differential case. 18. The variable gear ratio differential limiting device according to claim 17, wherein the gear ratio between the pinion and the pair of side gears varies during engagement between the pinion and the pair of side gears. 18. The variable gear ratio differential limiting device according to claim 17, wherein each of the pair of side gears is configured to rotate at different rotational speeds. Determining a desired torque bias and a desired portion of torque to transmit to the first gear;
Determining a defined movement of the operating surface to produce the desired torque bias and a desired portion of torque to be transmitted to the first gear;
Determining contact points between the first gear and the second gear defined by the operating surface; And
Determining the sprinkling surface of the first and second gears corresponding to the contact points defined by the actuating surface.

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